Indicator.



C. J. KELLEFL.

INDICATOR.

, APPLICATION ElLED MAR. 19.. 1918.

2 SHEETS-SHEET I.

INVENTOR WI NESSES fir ATTORNEY Patented A r. 8,1919.

C. I. KELLER.

INDICATOR.

APPLICATION FILED MAR. 19.. I918.

1299,3& Patented Apr. 8,1919.

' 2 SHEETSSHEET 2.

disposed Within said CLARENCE J". KELLER, F COLUMBUS, OHIO.

INDICATOR.

Specification of Letters Patent.

Patented Apr. 8, 1919.

Application filediflarch 19, 1918. Serial No. 223,418.

To all whom it may concern:

Be it known that I, CLARENCE J. KELLER, a citizen .of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented certain new and useful Improvements in Indicators, of which the following is a specification;

This invention relates to geometrical in struments, and more especially to those having a single contact for measuring distance; and the object of the same is to produce, an indicator whiclf' is useful in the protection of duplicate parts of standard size, while the parts are turned out by a tool which is in constant touch with the work.

The invention comprises a dial indicator mounted on one end of a barrel which in turn is carried by a holder fixed upon or adapted to be engaged with the bed of the machine, the plunger carrying a tool bearin on the rotating work whether the latter is being ground or turned; and details of its construction are set forth in the following specification and claims, and shown in the drawings, wherein Figure 1 is a side elevation of this instrument mounted in a holder, the latter discavity 3 and yet further enlarged and threaded at its upper extremity as at 4. The barrel at its lower end carries an out standing bracket 5 forked as shown at 6 and within the fork is pivoted at 7 a clamp 8 which has co-acting jaws 9 adapted to be drawn together by a screw 10. Between the 'aws when thus adjusted is held a jewel older or setting 11 in which is rigidly mounted a jewel such as a diamond 12. The lower extremity of the plunger 13 which is bore projec'ts beneath the barrel proper and is rounded as at 1 1 where it rests upon clamp 8. The weight of the latter is sustained by a spring 15 as best seen in Fig. 2. The plunger 13 rises loosely through the bore2 of the barrel, through a washer 16 at the lower end of the cavity 3, and through a coiled spring 17 which rests on said washer. It receives a nut 18 and a jam nut 19 above the spring, the function of which usually provided at the back of the upper side of the latter is therefore to sustain the weight of the plunger. A clamp 20 loosely surrounds the upper end of the barrel and carries an upstanding arm 21 having a pair of knuckles 22, and between the latter is -movably mounted a single knuckle 23 which is a dial indicator 24 of standard pattern, such as that made by Brown and Sharpe. As herein shown, this indicator has a setting knob 25 at its top by means of which the index 26 can be set to zero on the dial 27, and it has a stem 28 at the bottom through which is,

slidably mounted its plunger 29, the same by preference having a set screw 30 at its lower end which contacts with the rounded upper end 31 of the main plunger 13. The tubular stem 28 is disposed within a plug 32 which engagesthe threads 1 in the upper end of the. enlarged bore of the barrel, and after the parts have been set and adjusted the tightening of the screw 33 in the clamp 20 holds them so. The dial is graduated in thousandths and perhaps in ten-thousandths of an inch, according to the'make of the indicator, and the index shows the fine adustment outward of the indicator plunger 29. Thiselement is of course pushed upward bythe corresponding movement of the main plunger 13 whose uppefiend 31 contacts with the set screw 30 within the cavity 3 where no particles of dust or extraneous matter can possibly enter, and the main plunger is raised by the pivoted clamp 8 which in turn is lifted by some article contacting with the jewel 12.

This instrumentis intended for use in the production of duplicate parts such, for instance, as wrist pins for automobiles. Let us assume that these pins have been made in .the rough by casting, forging orotherwise,

have been turned, and are being finished one by one in a Landis grinder which is not necessary of illustration excepting where I have indicated its bed -10 in Fig. 1. Upon said bed I dispose a holder, here shown as having a foot 41 overlying hook 42 fitting closely against the front edge of the same, the foot being held in place by a bolt 43 passing downwardly through the bed itself. From such foot rises anarm 1 1 having at its upper end a head 45 ,bored obliquely as at 46 to receive the barrel 1, and a set screw 17 holds said barrel after it has been inserted through the bore and properly adjusted. This is butthe bed and a the combination with a one of many uses to which the invention has been put, and is described in its application to a grinding machine where the wrist pin is in constant touch with the grinder and it is desired to give it a standard exterior configuration of great accuracy.

The indicator is set to the working point of the. piece projecting, and after one piece is ground and measured with a micrometer, the dial of the indicator can beset to zero, and thereafter pieces ground can be easily duplicated by continuing the grinding application until the diameter is reduced to a point where the index points again to zero on the dial. Thus it will be seen that the use ofthe instrument avoids the necessity of frequent and repeated measuring of the device by micrometers and calipers, and yet assists the Workman in producing finished articles of great nicety and standard sizes because the jewel 12 stands in constant con tact with the face of the rotating work which is growing smaller as it is ground away, and the dial'is directly under his ob servation so that the least fluctuations of the index are noticeable immediately.

it is quite possible that the holder be not fixedly mounted on the bed 40 as it is obvious that when it is desired to measure the work, the instrument and holder can be brought into place and the foot 41 laid over the bed with the hook 42 against the rear edge of the same, provided no particles of metal intervene to destroy the accuracy of its location. lit might be possible to have the entire holder adjustable longitudinally of the bed, the latter usuallyv having a slot groove which could be taken advent; e of. But the adjustment of the barrel within the bore 46 beneath the set screw, and the adjustment of the contact between the two plungers by means of the screw 30, as well as the setting of the dial in the indicator, having once been accomplished on a pattern of work which it is desired to duplicats in numbers. should not be interrupted for reasons which will be obvious. I do not wish to limit myself to details further than set forth in the appended claims, nor to the materials and exact proportions of parts other than are necessary to carry out the broad idea. i

lNhile l have shown and described the instrument as mounted in a holder, it is of course quite possible that it could be fastened to the table or the head of a machine in which work is being handled, and the result would be practically the same so long as the contacting point or diamond 12 is in constant. contact with the work being turned, ground, or otherwise treated.

What is claimed as new is 1. In an instrument of the type described, tubularbarrel. a bracket at its lower end, a clamp pivoted at on said clamp,

for guiding its end and having an naeaeea one extremity in said bracket and having a pair of jaws, a jewel holder mounted between said jaws, and yielding means for drawing the clamp and holder toward the barrel; of a plunger movably mounted through the bore of the barrel and resting an indicator carried in the other end of the barrel and having an adjustable plunger projecting into said bore, and means for adjusting the contact between the meeting ends or" said plungers.

2. In an instrument of the type described, the combination with a tubular barrel, a bracket at its lower end, a clamp pivoted at one extremity in said bracket and havin a pair of jaws, a. jewel holder mounted etween said jaws, and yielding means for drawing the clamp and holder toward the barrel; of a plunger loosely mounted in the bore of said barrel and having its lower endv rounded and resting on said clamp, means upper end within said bore, an indicator mounted in the upper end of the barrel and having a plunger projecting into said bore, and a contact adjustably mounted in the lower end of the indicatorplunger and making contact with the upper end of the main plunger.

3. In an instrument of the class described, the combination with a tubular barrel having the upper end of its bore threaded, a plunger movably mounted in said bore and projecting below the barrel, a movable clamp attached to the barrel and carrying a ewel, yielding means for drawing the 100 clamp and jewel toward the barrel, and yielding means in the barrel for sustaining the weight ofthe plunger; of a tubular plug screwed into the upper end of said barrel, an indicator mounted on the lat- 105 ter and having a stem projecting through saidrplug and a plunger movably mounted through said stem, and means adjusting the contact between the inner ends of the plungers.

4. in an instrument of the classdescribed, the combination with tubular barrel having the upper end or" its bore threaded, a plunger movably mounted in said here and projecting below the clamp attached to the barrel and carrying a jewel, yielding means for drawing the clamp and jewel toward the barrel, and yielding means in the barrel for sustaining the weight of the plunger; of a plug movably mounted in the threaded up per end of the barrel, a clamp inclosing this upstanding arm, an in dicator having a casing connected with said arm and a stem -roectin down throu h 12s plug and a plunger through stern, and an adjustable contact between the meeting ends of said plungers.

In an instrument of thetype described,

the combination with a. plunger bore 136 barrel, a movable tubular 12d is enlarged at its upper end into a cavity, a washer at the base of said cav1ty,-a plunger mounted loosely in the bore and extending into the cavity, a nut adjustable on the on the upper end of the barrel with its plunger nro ecting IIItOSQ-ld cavity, and an adiustable contact between the meeting ends of said plungers.

6. In an instrument of the type described, the combination with a plunger whose here i enlarged at its upper end into a cavity, a washer at the baseof said cavity, a plunger mounted loosely in the bore and extend ing into the cavity, a nut adjustable on the upper end of the plunger, an expansive spring between the nut and washer, a movable jewel holder carried by the lower end of the barrel, and yielding means holding it in contact with the lower extremity of the plunger; of a clamp surrounding the upper end of the barrel, an indicator whose casing .is carried by said clamp, a guide within said end for the indicator-plunger, and an adjustable contact between the meeting ends of said plungers.

In testimony whereof I afiix my signature in presence of two witnesses.

CLARENCE J. KELLER.

Witnesses:

GEORGE D. BAROK, IHORATIO S. ATEHUM. 

